Thermos flask

How do these flasks work to keep drinks at a constant temperature?

Material processes - Changing materials - Insulation

Learning Points
Thermal insulators do not allow heat energy to flow easily through them.

Vacuums are insulators because they have no molecules for heat transfer.

A Twig Context Film. Reinforce and extend the learning required by the curriculum. Twig’s context films show abstract concepts in action in the real world.